Add folder synchronization status.

Also add ability to force re-synchronization.

10 files changed, 610 insertions, 40 deletions

diff --git a/lib/apiv1/apiv1.go b/lib/apiv1/apiv1.go
index f32e53b..262f513 100644
--- a/lib/apiv1/apiv1.go
+++ b/lib/apiv1/apiv1.go
@@ -42,6 +42,7 @@ func New(r *gin.Engine, sess *session.Sessions, cfg *xdsconfig.Config, mfolders
 	s.apiRouter.GET("/folders", s.getFolders)
 	s.apiRouter.GET("/folder/:id", s.getFolder)
 	s.apiRouter.POST("/folder", s.addFolder)
+	s.apiRouter.POST("/folder/sync/:id", s.syncFolder)
 	s.apiRouter.DELETE("/folder/:id", s.delFolder)
 
 	s.apiRouter.GET("/sdks", s.getSdks)
@@ -54,5 +55,9 @@ func New(r *gin.Engine, sess *session.Sessions, cfg *xdsconfig.Config, mfolders
 	s.apiRouter.POST("/exec/:id", s.execCmd)
 	s.apiRouter.POST("/signal", s.execSignalCmd)
 
+	s.apiRouter.GET("/events", s.eventsList)
+	s.apiRouter.POST("/events/register", s.eventsRegister)
+	s.apiRouter.POST("/events/unregister", s.eventsUnRegister)
+
 	return s
 }
diff --git a/lib/apiv1/events.go b/lib/apiv1/events.go
new file mode 100644
index 0000000..da8298c
--- /dev/null
+++ b/lib/apiv1/events.go
@@ -0,0 +1,147 @@
+package apiv1
+
+import (
+	"net/http"
+	"time"
+
+	"github.com/iotbzh/xds-server/lib/folder"
+
+	"github.com/gin-gonic/gin"
+	common "github.com/iotbzh/xds-common/golib"
+)
+
+// EventArgs is the parameters (json format) of /events/register command
+type EventRegisterArgs struct {
+	Name      string `json:"name"`
+	ProjectID string `json:"filterProjectID"`
+}
+
+type EventUnRegisterArgs struct {
+	Name string `json:"name"`
+	ID   int    `json:"id"`
+}
+
+// EventMsg Message send
+type EventMsg struct {
+	Time   string              `json:"time"`
+	Type   string              `json:"type"`
+	Folder folder.FolderConfig `json:"folder"`
+}
+
+// EventEvent Event send in WS when an internal event (eg. Syncthing event is received)
+const EventEventAll = "event:all"
+const EventEventType = "event:" // following by event type
+
+// eventsList Registering for events that will be send over a WS
+func (s *APIService) eventsList(c *gin.Context) {
+
+}
+
+// eventsRegister Registering for events that will be send over a WS
+func (s *APIService) eventsRegister(c *gin.Context) {
+	var args EventRegisterArgs
+
+	if c.BindJSON(&args) != nil {
+		common.APIError(c, "Invalid arguments")
+		return
+	}
+
+	sess := s.sessions.Get(c)
+	if sess == nil {
+		common.APIError(c, "Unknown sessions")
+		return
+	}
+
+	evType := "FolderStateChanged"
+	if args.Name != evType {
+		common.APIError(c, "Unsupported event name")
+		return
+	}
+
+	/* XXX - to be removed if no plan to support "generic" event
+	var cbFunc st.EventsCB
+	cbFunc = func(ev st.Event, data *st.EventsCBData) {
+
+		evid, _ := strconv.Atoi((*data)["id"].(string))
+		ssid := (*data)["sid"].(string)
+		so := s.sessions.IOSocketGet(ssid)
+		if so == nil {
+			s.log.Infof("Event %s not emitted - sid: %s", ev.Type, ssid)
+
+			// Consider that client disconnected, so unregister this event
+			s.mfolders.SThg.Events.UnRegister(ev.Type, evid)
+			return
+		}
+
+		msg := EventMsg{
+			Time: ev.Time,
+			Type: ev.Type,
+			Data: ev.Data,
+		}
+
+		if err := (*so).Emit(EventEventAll, msg); err != nil {
+			s.log.Errorf("WS Emit Event : %v", err)
+		}
+
+		if err := (*so).Emit(EventEventType+ev.Type, msg); err != nil {
+			s.log.Errorf("WS Emit Event : %v", err)
+		}
+	}
+
+	data := make(st.EventsCBData)
+	data["sid"] = sess.ID
+
+	id, err := s.mfolders.SThg.Events.Register(args.Name, cbFunc, args.ProjectID, &data)
+	*/
+
+	var cbFunc folder.EventCB
+	cbFunc = func(cfg *folder.FolderConfig, data *folder.EventCBData) {
+		ssid := (*data)["sid"].(string)
+		so := s.sessions.IOSocketGet(ssid)
+		if so == nil {
+			//s.log.Infof("Event %s not emitted - sid: %s", ev.Type, ssid)
+
+			// Consider that client disconnected, so unregister this event
+			// SEB FIXMEs.mfolders.RegisterEventChange(ev.Type)
+			return
+		}
+
+		msg := EventMsg{
+			Time:   time.Now().String(),
+			Type:   evType,
+			Folder: *cfg,
+		}
+
+		if err := (*so).Emit(EventEventType+evType, msg); err != nil {
+			s.log.Errorf("WS Emit Folder StateChanged event : %v", err)
+		}
+	}
+	data := make(folder.EventCBData)
+	data["sid"] = sess.ID
+
+	err := s.mfolders.RegisterEventChange(args.ProjectID, &cbFunc, &data)
+	if err != nil {
+		common.APIError(c, err.Error())
+		return
+	}
+
+	c.JSON(http.StatusOK, gin.H{"status": "OK"})
+}
+
+// eventsRegister Registering for events that will be send over a WS
+func (s *APIService) eventsUnRegister(c *gin.Context) {
+	var args EventUnRegisterArgs
+
+	if c.BindJSON(&args) != nil || args.Name == "" || args.ID < 0 {
+		common.APIError(c, "Invalid arguments")
+		return
+	}
+	/* TODO
+	if err := s.mfolders.SThg.Events.UnRegister(args.Name, args.ID); err != nil {
+		common.APIError(c, err.Error())
+		return
+	}
+	c.JSON(http.StatusOK, gin.H{"status": "OK"})
+	*/
+	common.APIError(c, "Not implemented yet")
+}
diff --git a/lib/apiv1/folders.go b/lib/apiv1/folders.go
index f957c6d..cf56c3f 100644
--- a/lib/apiv1/folders.go
+++ b/lib/apiv1/folders.go
@@ -43,6 +43,21 @@ func (s *APIService) addFolder(c *gin.Context) {
 	c.JSON(http.StatusOK, newFld)
 }
 
+// syncFolder force synchronization of folder files
+func (s *APIService) syncFolder(c *gin.Context) {
+	id := c.Param("id")
+
+	s.log.Debugln("Sync folder id: ", id)
+
+	err := s.mfolders.ForceSync(id)
+	if err != nil {
+		common.APIError(c, err.Error())
+		return
+	}
+
+	c.JSON(http.StatusOK, "")
+}
+
 // delFolder deletes folder from server config
 func (s *APIService) delFolder(c *gin.Context) {
 	id := c.Param("id")
@@ -55,5 +70,4 @@ func (s *APIService) delFolder(c *gin.Context) {
 		return
 	}
 	c.JSON(http.StatusOK, delEntry)
-
 }
diff --git a/lib/folder/folder-interface.go b/lib/folder/folder-interface.go
index b76b3f3..c04cbd7 100644
--- a/lib/folder/folder-interface.go
+++ b/lib/folder/folder-interface.go
@@ -14,16 +14,24 @@ const (
 	StatusErrorConfig = "ErrorConfig"
 	StatusDisable     = "Disable"
 	StatusEnable      = "Enable"
+	StatusPause       = "Pause"
+	StatusSyncing     = "Syncing"
 )
 
+type EventCBData map[string]interface{}
+type EventCB func(cfg *FolderConfig, data *EventCBData)
+
 // IFOLDER Folder interface
 type IFOLDER interface {
-	Add(cfg FolderConfig) (*FolderConfig, error) // Add a new folder
-	GetConfig() FolderConfig                     // Get folder public configuration
-	GetFullPath(dir string) string               // Get folder full path
-	Remove() error                               // Remove a folder
-	Sync() error                                 // Force folder files synchronization
-	IsInSync() (bool, error)                     // Check if folder files are in-sync
+	NewUID(suffix string) string                              // Get a new folder UUID
+	Add(cfg FolderConfig) (*FolderConfig, error)              // Add a new folder
+	GetConfig() FolderConfig                                  // Get folder public configuration
+	GetFullPath(dir string) string                            // Get folder full path
+	Remove() error                                            // Remove a folder
+	RegisterEventChange(cb *EventCB, data *EventCBData) error // Request events registration (sent through WS)
+	UnRegisterEventChange() error                             // Un-register events
+	Sync() error                                              // Force folder files synchronization
+	IsInSync() (bool, error)                                  // Check if folder files are in-sync
 }
 
 // FolderConfig is the config for one folder
@@ -33,6 +41,7 @@ type FolderConfig struct {
 	ClientPath string     `json:"path"`
 	Type       FolderType `json:"type"`
 	Status     string     `json:"status"`
+	IsInSync   bool       `json:"isInSync"`
 	DefaultSdk string     `json:"defaultSdk"`
 
 	// Not exported fields from REST API point of view
diff --git a/lib/folder/folder-pathmap.go b/lib/folder/folder-pathmap.go
index 2ad8a93..f73f271 100644
--- a/lib/folder/folder-pathmap.go
+++ b/lib/folder/folder-pathmap.go
@@ -8,6 +8,7 @@ import (
 
 	common "github.com/iotbzh/xds-common/golib"
 	"github.com/iotbzh/xds-server/lib/xdsconfig"
+	uuid "github.com/satori/go.uuid"
 )
 
 // IFOLDER interface implementation for native/path mapping folders
@@ -26,6 +27,11 @@ func NewFolderPathMap(gc *xdsconfig.Config) *PathMap {
 	return &f
 }
 
+// NewUID Get a UUID
+func (f *PathMap) NewUID(suffix string) string {
+	return uuid.NewV1().String() + "_" + suffix
+}
+
 // Add a new folder
 func (f *PathMap) Add(cfg FolderConfig) (*FolderConfig, error) {
 	if cfg.DataPathMap.ServerPath == "" {
@@ -63,6 +69,7 @@ func (f *PathMap) Add(cfg FolderConfig) (*FolderConfig, error) {
 	f.config = cfg
 	f.config.RootPath = dir
 	f.config.DataPathMap.ServerPath = dir
+	f.config.IsInSync = true
 	f.config.Status = StatusEnable
 
 	return &f.config, nil
@@ -87,6 +94,16 @@ func (f *PathMap) Remove() error {
 	return nil
 }
 
+// RegisterEventChange requests registration for folder change event
+func (f *PathMap) RegisterEventChange(cb *EventCB, data *EventCBData) error {
+	return nil
+}
+
+// UnRegisterEventChange remove registered callback
+func (f *PathMap) UnRegisterEventChange() error {
+	return nil
+}
+
 // Sync Force folder files synchronization
 func (f *PathMap) Sync() error {
 	return nil
diff --git a/lib/model/folders.go b/lib/model/folders.go
index 02c3254..ed0078e 100644
--- a/lib/model/folders.go
+++ b/lib/model/folders.go
@@ -7,13 +7,13 @@ import (
 	"os"
 	"path/filepath"
 	"strings"
+	"time"
 
 	"github.com/Sirupsen/logrus"
 	common "github.com/iotbzh/xds-common/golib"
 	"github.com/iotbzh/xds-server/lib/folder"
 	"github.com/iotbzh/xds-server/lib/syncthing"
 	"github.com/iotbzh/xds-server/lib/xdsconfig"
-	uuid "github.com/satori/go.uuid"
 	"github.com/syncthing/syncthing/lib/sync"
 )
 
@@ -24,6 +24,12 @@ type Folders struct {
 	Log        *logrus.Logger
 	SThg       *st.SyncThing
 	folders    map[string]*folder.IFOLDER
+	registerCB []RegisteredCB
+}
+
+type RegisteredCB struct {
+	cb   *folder.EventCB
+	data *folder.EventCBData
 }
 
 // Mutex to make add/delete atomic
@@ -39,6 +45,7 @@ func FoldersNew(cfg *xdsconfig.Config, st *st.SyncThing) *Folders {
 		Log:        cfg.Log,
 		SThg:       st,
 		folders:    make(map[string]*folder.IFOLDER),
+		registerCB: []RegisteredCB{},
 	}
 }
 
@@ -114,12 +121,15 @@ func (f *Folders) LoadConfig() error {
 	// Update folders
 	f.Log.Infof("Loading initial folders config: %d folders found", len(flds))
 	for _, fc := range flds {
-		if _, err := f.createUpdate(fc, false); err != nil {
+		if _, err := f.createUpdate(fc, false, true); err != nil {
 			return err
 		}
 	}
 
-	return nil
+	// Save config on disk
+	err := f.SaveConfig()
+
+	return err
 }
 
 // SaveConfig Save folders configuration to disk
@@ -164,11 +174,11 @@ func (f *Folders) getConfigArrUnsafe() []folder.FolderConfig {
 
 // Add adds a new folder
 func (f *Folders) Add(newF folder.FolderConfig) (*folder.FolderConfig, error) {
-	return f.createUpdate(newF, true)
+	return f.createUpdate(newF, true, false)
 }
 
 // CreateUpdate creates or update a folder
-func (f *Folders) createUpdate(newF folder.FolderConfig, create bool) (*folder.FolderConfig, error) {
+func (f *Folders) createUpdate(newF folder.FolderConfig, create bool, initial bool) (*folder.FolderConfig, error) {
 
 	fcMutex.Lock()
 	defer fcMutex.Unlock()
@@ -181,23 +191,7 @@ func (f *Folders) createUpdate(newF folder.FolderConfig, create bool) (*folder.F
 		return nil, fmt.Errorf("ClientPath must be set")
 	}
 
-	// Allocate a new UUID
-	if create {
-		newF.ID = uuid.NewV1().String()
-	}
-	if !create && newF.ID == "" {
-		return nil, fmt.Errorf("Cannot update folder with null ID")
-	}
-
-	// Set default value if needed
-	if newF.Status == "" {
-		newF.Status = folder.StatusDisable
-	}
-
-	if newF.Label == "" {
-		newF.Label = filepath.Base(newF.ClientPath) + "_" + newF.ID[0:8]
-	}
-
+	// Create a new folder object
 	var fld folder.IFOLDER
 	switch newF.Type {
 	// SYNCTHING
@@ -213,6 +207,26 @@ func (f *Folders) createUpdate(newF folder.FolderConfig, create bool) (*folder.F
 		return nil, fmt.Errorf("Unsupported folder type")
 	}
 
+	// Set default value if needed
+	if newF.Status == "" {
+		newF.Status = folder.StatusDisable
+	}
+	if newF.Label == "" {
+		newF.Label = filepath.Base(newF.ClientPath) + "_" + newF.ID[0:8]
+	}
+
+	// Allocate a new UUID
+	if create {
+		i := len(newF.Label)
+		if i > 20 {
+			i = 20
+		}
+		newF.ID = fld.NewUID(newF.Label[:i])
+	}
+	if !create && newF.ID == "" {
+		return nil, fmt.Errorf("Cannot update folder with null ID")
+	}
+
 	// Normalize path (needed for Windows path including bashlashes)
 	newF.ClientPath = common.PathNormalize(newF.ClientPath)
 
@@ -224,13 +238,31 @@ func (f *Folders) createUpdate(newF folder.FolderConfig, create bool) (*folder.F
 		return newFolder, err
 	}
 
-	// Register folder object
+	// Add to folders list
 	f.folders[newF.ID] = &fld
 
 	// Save config on disk
-	err = f.SaveConfig()
+	if !initial {
+		if err := f.SaveConfig(); err != nil {
+			return newFolder, err
+		}
+	}
+
+	// Register event change callback
+	for _, rcb := range f.registerCB {
+		if err := fld.RegisterEventChange(rcb.cb, rcb.data); err != nil {
+			return newFolder, err
+		}
+	}
+
+	// Force sync after creation
+	// (need to defer to be sure that WS events will arrive after HTTP creation reply)
+	go func() {
+		time.Sleep(time.Millisecond * 500)
+		fld.Sync()
+	}()
 
-	return newFolder, err
+	return newFolder, nil
 }
 
 // Delete deletes a specific folder
@@ -260,6 +292,29 @@ func (f *Folders) Delete(id string) (folder.FolderConfig, error) {
 	return fld, err
 }
 
+// RegisterEventChange requests registration for folder event change
+func (f *Folders) RegisterEventChange(id string, cb *folder.EventCB, data *folder.EventCBData) error {
+
+	flds := make(map[string]*folder.IFOLDER)
+	if id != "" {
+		// Register to a specific folder
+		flds[id] = f.Get(id)
+	} else {
+		// Register to all folders
+		flds = f.folders
+		f.registerCB = append(f.registerCB, RegisteredCB{cb: cb, data: data})
+	}
+
+	for _, fld := range flds {
+		err := (*fld).RegisterEventChange(cb, data)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
 // ForceSync Force the synchronization of a folder
 func (f *Folders) ForceSync(id string) error {
 	fc := f.Get(id)
diff --git a/lib/syncthing/folder-st.go b/lib/syncthing/folder-st.go
index ffcd284..da27062 100644
--- a/lib/syncthing/folder-st.go
+++ b/lib/syncthing/folder-st.go
@@ -6,6 +6,7 @@ import (
 
 	"github.com/iotbzh/xds-server/lib/folder"
 	"github.com/iotbzh/xds-server/lib/xdsconfig"
+	uuid "github.com/satori/go.uuid"
 	"github.com/syncthing/syncthing/lib/config"
 )
 
@@ -13,10 +14,13 @@ import (
 
 // STFolder .
 type STFolder struct {
-	globalConfig *xdsconfig.Config
-	st           *SyncThing
-	fConfig      folder.FolderConfig
-	stfConfig    config.FolderConfiguration
+	globalConfig      *xdsconfig.Config
+	st                *SyncThing
+	fConfig           folder.FolderConfig
+	stfConfig         config.FolderConfiguration
+	eventIDs          []int
+	eventChangeCB     *folder.EventCB
+	eventChangeCBData *folder.EventCBData
 }
 
 // NewFolderST Create a new instance of STFolder
@@ -27,6 +31,15 @@ func (s *SyncThing) NewFolderST(gc *xdsconfig.Config) *STFolder {
 	}
 }
 
+// NewUID Get a UUID
+func (f *STFolder) NewUID(suffix string) string {
+	i := len(f.st.MyID)
+	if i > 15 {
+		i = 15
+	}
+	return uuid.NewV1().String()[:14] + f.st.MyID[:i] + "_" + suffix
+}
+
 // Add a new folder
 func (f *STFolder) Add(cfg folder.FolderConfig) (*folder.FolderConfig, error) {
 
@@ -59,6 +72,16 @@ func (f *STFolder) Add(cfg folder.FolderConfig) (*folder.FolderConfig, error) {
 			return nil, err
 		}
 
+		// Register to events to update folder status
+		for _, evName := range []string{EventStateChanged, EventFolderPaused} {
+			evID, err := f.st.Events.Register(evName, f.cbEventState, id, nil)
+			if err != nil {
+				return nil, err
+			}
+			f.eventIDs = append(f.eventIDs, evID)
+		}
+
+		f.fConfig.IsInSync = false // will be updated later by events
 		f.fConfig.Status = folder.StatusEnable
 	}
 
@@ -86,6 +109,20 @@ func (f *STFolder) Remove() error {
 	return f.st.FolderDelete(f.stfConfig.ID)
 }
 
+// RegisterEventChange requests registration for folder event change
+func (f *STFolder) RegisterEventChange(cb *folder.EventCB, data *folder.EventCBData) error {
+	f.eventChangeCB = cb
+	f.eventChangeCBData = data
+	return nil
+}
+
+// UnRegisterEventChange remove registered callback
+func (f *STFolder) UnRegisterEventChange() error {
+	f.eventChangeCB = nil
+	f.eventChangeCBData = nil
+	return nil
+}
+
 // Sync Force folder files synchronization
 func (f *STFolder) Sync() error {
 	return f.st.FolderScan(f.stfConfig.ID, "")
@@ -93,5 +130,41 @@ func (f *STFolder) Sync() error {
 
 // IsInSync Check if folder files are in-sync
 func (f *STFolder) IsInSync() (bool, error) {
-	return f.st.IsFolderInSync(f.stfConfig.ID)
+	sts, err := f.st.IsFolderInSync(f.stfConfig.ID)
+	if err != nil {
+		return false, err
+	}
+	f.fConfig.IsInSync = sts
+	return sts, nil
+}
+
+// callback use to update IsInSync status
+func (f *STFolder) cbEventState(ev Event, data *EventsCBData) {
+	prevSync := f.fConfig.IsInSync
+	prevStatus := f.fConfig.Status
+
+	switch ev.Type {
+
+	case EventStateChanged:
+		to := ev.Data["to"]
+		switch to {
+		case "scanning", "syncing":
+			f.fConfig.Status = folder.StatusSyncing
+		case "idle":
+			f.fConfig.Status = folder.StatusEnable
+		}
+		f.fConfig.IsInSync = (to == "idle")
+
+	case EventFolderPaused:
+		if f.fConfig.Status == folder.StatusEnable {
+			f.fConfig.Status = folder.StatusPause
+		}
+		f.fConfig.IsInSync = false
+	}
+
+	if f.eventChangeCB != nil &&
+		(prevSync != f.fConfig.IsInSync || prevStatus != f.fConfig.Status) {
+		cpConf := f.fConfig
+		(*f.eventChangeCB)(&cpConf, f.eventChangeCBData)
+	}
 }
diff --git a/lib/syncthing/st.go b/lib/syncthing/st.go
index 9bdb48f..10210a4 100644
--- a/lib/syncthing/st.go
+++ b/lib/syncthing/st.go
@@ -42,6 +42,7 @@ type SyncThing struct {
 	conf        *xdsconfig.Config
 	client      *common.HTTPClient
 	log         *logrus.Logger
+	Events      *Events
 }
 
 // ExitChan Channel used for process exit
@@ -126,6 +127,9 @@ func NewSyncThing(conf *xdsconfig.Config, log *logrus.Logger) *SyncThing {
 		conf:    conf,
 	}
 
+	// Create Events monitoring
+	s.Events = s.NewEventListener()
+
 	return &s
 }
 
@@ -316,6 +320,12 @@ func (s *SyncThing) Connect() error {
 	s.client.SetLogger(s.log)
 
 	s.MyID, err = s.IDGet()
+	if err != nil {
+		return fmt.Errorf("ERROR: cannot retrieve ID")
+	}
+
+	// Start events monitoring
+	err = s.Events.Start()
 
 	return err
 }
diff --git a/lib/syncthing/stEvent.go b/lib/syncthing/stEvent.go
new file mode 100644
index 0000000..bf2a809
--- /dev/null
+++ b/lib/syncthing/stEvent.go
@@ -0,0 +1,242 @@
+package st
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/Sirupsen/logrus"
+)
+
+// Events .
+type Events struct {
+	MonitorTime time.Duration
+	Debug       bool
+
+	stop  chan bool
+	st    *SyncThing
+	log   *logrus.Logger
+	cbArr map[string][]cbMap
+}
+
+type Event struct {
+	Type string            `json:"type"`
+	Time time.Time         `json:"time"`
+	Data map[string]string `json:"data"`
+}
+
+type EventsCBData map[string]interface{}
+type EventsCB func(ev Event, cbData *EventsCBData)
+
+const (
+	EventFolderCompletion string = "FolderCompletion"
+	EventFolderSummary    string = "FolderSummary"
+	EventFolderPaused     string = "FolderPaused"
+	EventFolderResumed    string = "FolderResumed"
+	EventFolderErrors     string = "FolderErrors"
+	EventStateChanged     string = "StateChanged"
+)
+
+var EventsAll string = EventFolderCompletion + "|" +
+	EventFolderSummary + "|" +
+	EventFolderPaused + "|" +
+	EventFolderResumed + "|" +
+	EventFolderErrors + "|" +
+	EventStateChanged
+
+type STEvent struct {
+	// Per-subscription sequential event ID. Named "id" for backwards compatibility with the REST API
+	SubscriptionID int `json:"id"`
+	// Global ID of the event across all subscriptions
+	GlobalID int                    `json:"globalID"`
+	Time     time.Time              `json:"time"`
+	Type     string                 `json:"type"`
+	Data     map[string]interface{} `json:"data"`
+}
+
+type cbMap struct {
+	id       int
+	cb       EventsCB
+	filterID string
+	data     *EventsCBData
+}
+
+// NewEventListener Create a new instance of Event listener
+func (s *SyncThing) NewEventListener() *Events {
+	_, dbg := os.LookupEnv("XDS_DEBUG_STEVENTS") // set to add more debug log
+	return &Events{
+		MonitorTime: 100, // in Milliseconds
+		Debug:       dbg,
+		stop:        make(chan bool, 1),
+		st:          s,
+		log:         s.log,
+		cbArr:       make(map[string][]cbMap),
+	}
+}
+
+// Start starts event monitoring loop
+func (e *Events) Start() error {
+	go e.monitorLoop()
+	return nil
+}
+
+// Stop stops event monitoring loop
+func (e *Events) Stop() {
+	e.stop <- true
+}
+
+// Register Add a listener on an event
+func (e *Events) Register(evName string, cb EventsCB, filterID string, data *EventsCBData) (int, error) {
+	if evName == "" || !strings.Contains(EventsAll, evName) {
+		return -1, fmt.Errorf("Unknown event name")
+	}
+	if data == nil {
+		data = &EventsCBData{}
+	}
+
+	cbList := []cbMap{}
+	if _, ok := e.cbArr[evName]; ok {
+		cbList = e.cbArr[evName]
+	}
+
+	id := len(cbList)
+	(*data)["id"] = strconv.Itoa(id)
+
+	e.cbArr[evName] = append(cbList, cbMap{id: id, cb: cb, filterID: filterID, data: data})
+
+	return id, nil
+}
+
+// UnRegister Remove a listener event
+func (e *Events) UnRegister(evName string, id int) error {
+	cbKey, ok := e.cbArr[evName]
+	if !ok {
+		return fmt.Errorf("No event registered to such name")
+	}
+
+	// FIXME - NOT TESTED
+	if id >= len(cbKey) {
+		return fmt.Errorf("Invalid id")
+	} else if id == len(cbKey) {
+		e.cbArr[evName] = cbKey[:id-1]
+	} else {
+		e.cbArr[evName] = cbKey[id : id+1]
+	}
+
+	return nil
+}
+
+// GetEvents returns the Syncthing events
+func (e *Events) getEvents(since int) ([]STEvent, error) {
+	var data []byte
+	ev := []STEvent{}
+	url := "events"
+	if since != -1 {
+		url += "?since=" + strconv.Itoa(since)
+	}
+	if err := e.st.client.HTTPGet(url, &data); err != nil {
+		return ev, err
+	}
+	err := json.Unmarshal(data, &ev)
+	return ev, err
+}
+
+// Loop to monitor Syncthing events
+func (e *Events) monitorLoop() {
+	e.log.Infof("Event monitoring running...")
+	since := 0
+	for {
+		select {
+		case <-e.stop:
+			e.log.Infof("Event monitoring exited")
+			return
+
+		case <-time.After(e.MonitorTime * time.Millisecond):
+			stEvArr, err := e.getEvents(since)
+			if err != nil {
+				e.log.Errorf("Syncthing Get Events: %v", err)
+				continue
+			}
+			// Process events
+			for _, stEv := range stEvArr {
+				since = stEv.SubscriptionID
+				if e.Debug {
+					e.log.Warnf("ST EVENT: %d %s\n  %v", stEv.GlobalID, stEv.Type, stEv)
+				}
+
+				cbKey, ok := e.cbArr[stEv.Type]
+				if !ok {
+					continue
+				}
+
+				evData := Event{
+					Type: stEv.Type,
+					Time: stEv.Time,
+				}
+
+				// Decode Events
+				// FIXME: re-define data struct for each events
+				// instead of map of string and use JSON marshing/unmarshing
+				fID := ""
+				evData.Data = make(map[string]string)
+				switch stEv.Type {
+
+				case EventFolderCompletion:
+					fID = convString(stEv.Data["folder"])
+					evData.Data["completion"] = convFloat64(stEv.Data["completion"])
+
+				case EventFolderSummary:
+					fID = convString(stEv.Data["folder"])
+					evData.Data["needBytes"] = convInt64(stEv.Data["needBytes"])
+					evData.Data["state"] = convString(stEv.Data["state"])
+
+				case EventFolderPaused, EventFolderResumed:
+					fID = convString(stEv.Data["id"])
+					evData.Data["label"] = convString(stEv.Data["label"])
+
+				case EventFolderErrors:
+					fID = convString(stEv.Data["folder"])
+					// TODO decode array evData.Data["errors"] = convString(stEv.Data["errors"])
+
+				case EventStateChanged:
+					fID = convString(stEv.Data["folder"])
+					evData.Data["from"] = convString(stEv.Data["from"])
+					evData.Data["to"] = convString(stEv.Data["to"])
+
+				default:
+					e.log.Warnf("Unsupported event type")
+				}
+
+				if fID != "" {
+					evData.Data["id"] = fID
+				}
+
+				// Call all registered callbacks
+				for _, c := range cbKey {
+					if e.Debug {
+						e.log.Warnf("EVENT CB fID=%s, filterID=%s", fID, c.filterID)
+					}
+					// Call when filterID is not set or when it matches
+					if c.filterID == "" || (fID != "" && fID == c.filterID) {
+						c.cb(evData, c.data)
+					}
+				}
+			}
+		}
+	}
+}
+
+func convString(d interface{}) string {
+	return d.(string)
+}
+
+func convFloat64(d interface{}) string {
+	return strconv.FormatFloat(d.(float64), 'f', -1, 64)
+}
+
+func convInt64(d interface{}) string {
+	return strconv.FormatInt(d.(int64), 10)
+}
diff --git a/lib/syncthing/stfolder.go b/lib/syncthing/stfolder.go
index bbdcc43..70ac70a 100644
--- a/lib/syncthing/stfolder.go
+++ b/lib/syncthing/stfolder.go
@@ -191,13 +191,11 @@ func (s *SyncThing) FolderStatus(folderID string) (*FolderStatus, error) {
 
 // IsFolderInSync Returns true when folder is in sync
 func (s *SyncThing) IsFolderInSync(folderID string) (bool, error) {
-	// FIXME better to detected FolderCompletion event (/rest/events)
-	// See https://docs.syncthing.net/dev/events.html
 	sts, err := s.FolderStatus(folderID)
 	if err != nil {
 		return false, err
 	}
-	return sts.NeedBytes == 0, nil
+	return sts.NeedBytes == 0 && sts.State == "idle", nil
 }
 
 // FolderScan Request immediate folder scan.